From 108d01c3efda55d63193f33e29fb878b07313dfc Mon Sep 17 00:00:00 2001 From: Robert Peterson Date: Thu, 18 Apr 2019 07:41:38 -0700 Subject: Add list:index_map --- gen/src/list.erl | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-) (limited to 'gen/src') diff --git a/gen/src/list.erl b/gen/src/list.erl index 10a093a..36fb42d 100644 --- a/gen/src/list.erl +++ b/gen/src/list.erl @@ -1,7 +1,7 @@ -module(list). -compile(no_auto_import). --export([length/1, reverse/1, is_empty/1, contains/2, head/1, tail/1, filter/2, map/2, traverse/2, drop/2, take/2, new/0, append/2, flatten/1, fold/3, fold_right/3, find/2, all/2, any/2, zip/2, intersperse/2, at/2, unique/1, sort/1]). +-export([length/1, reverse/1, is_empty/1, contains/2, head/1, tail/1, filter/2, map/2, index_map/2, traverse/2, drop/2, take/2, new/0, append/2, flatten/1, fold/3, fold_right/3, find/2, all/2, any/2, zip/2, intersperse/2, at/2, unique/1, sort/1]). length(A) -> erlang:length(A). @@ -70,6 +70,18 @@ do_map(List, Fun, Acc) -> map(List, Fun) -> do_map(List, Fun, []). +do_index_map(List, Fun, Index, Acc) -> + case List of + [] -> + reverse(Acc); + + [X | Xs] -> + do_index_map(Xs, Fun, Index + 1, [Fun(Index, X) | Acc]) + end. + +index_map(List, Fun) -> + do_index_map(List, Fun, 0, []). + do_traverse(List, Fun, Acc) -> case List of [] -> -- cgit v1.2.3